Vacuum device



ov- 3 F. w. HOCHSYTETTER I VACUUM DEVICE Filed Dec. 4. 1929 2Sheets-Sheet 1 i s Z" 8 Dm/ecfnc Z UHZHU Mu E31 z Fmdemk w. hochfefferNov/22, 1932. F. w. HOCHSTETTER 1,888,594

' VACUUM DEVICE Filed Dec, 4, ;929 2 Sheets-Sheet 2 avwwto'c PatentedNov. 22 1932 UNITED STATES VACUUM DEVICE Application filed December4,-1929. Seria1'No.41i,408. i

This invention relates in general to improvements in vacuum devices ofthe type now generally known as audions.

One of the objects of this invention is to provide in multi-electrodeaudions, novel features of construction, particularly in connection withaudions in which the grid or control electrode is dielectricallyisolated from the other electrodes.

Another object of this invention is the provision of a construction bymeans of which the grid is so isolated.

A still further object of this invention is the provision of aconstruction in audions in which the grid is arranged with respect tothe plate so that the electrons in moving to the plate pass by the gridwithout having their paths of movement intersect the grid.

Another object of this invention is the provision of a corrugated plateelectrode in a vacuum device of this type which permits of a plate oflarge area to receive electrons with respect to the space occupied byit.

Another object of this invention is to associate the cathode and plateof an electron discharge deviceso that the electrons can flow betweenthem without passing through the grid.

These and other objects as will appear from the following descriptionare secured by means of this invention.

This invention resides substantially in the combination, construction,arrangement and relative location of parts, all as will be described inconsiderable detail below.

Referring to the drawings;

Figure 1 is a view of one form of the device with some parts brokenaway, and other parts in cross section;

Fig. 2 is a similar view of a modified form of the device;

Fig. 3 illustrates a still further modification; and

Fig. 4 illustrates a third modification.

The principles of construction and operation underlying the vacuumdevices of this invention are first a dielectric isolation of the gridwith respect to the other electrodes, an arrangement of the electrodesso that the electrons do not flow through the grid, the interposition ofa dielectric between the grid and cathode so that 'no grid currentcanflow, and by the construction the elimination of the necessity ofrusingfa grid bias in circuits associated therewith. The best understand-:1.

ing of the 'invention'may be had by dir'ct'ref erence to the drawings. i

Referring. toiFig. '1. the, device isshowir comprising a base 1 andthe-usual contact prongs 2 depending therefrom. Securedto the base inthe "usual and .well known "man? ner is the evacuated pointed out'thatin all forms of 'devices'x'disclosed, the base, prongs and glass shellare the same. Each tube is provided with a reentrant glass supportingstem 4 of the usual construction. The filament 6 in the device disclosedin Fig. 1 is of the so-called hard pin type surrounded by a wire grid 8.Interposed between the filament and grid is an open ended shield 7 ofsuitable dielectric'or insulating material such as mica, fiber and thelike. Placed above these elements is the corrugated plate electrode 9.The filament grid plate and shield are all separated from the stem 4. Vy

In the modification shown in Fig. 2 the glass shell'3. It mayibfefilament 6 is horizontal which has the advantage that the hot spot mentis eliminated.

In the form of device shown in Fig. 3 the plate 9 surrounds the otherelements andthe filament is supported by the hook bracket 10 in the wellknown manner.

. In the modification shown in Fig. 4 the filament 6 consists of astraight horizontal portion above which is supported a piece ofdielectric material 7 and on which is in turn supported the grid 8. Theplate '9 is suptendency of the fila ported above the grid as shown. v Bythe use 7 of the dielectric supporting wall the necessity of a grid biasis eliminated sincethe electrons cannot flow to the grid during theposi- V tive halfof the single cycle. Instead of corrugating the plateas shown in Figs. 1 and 2, the plate may be roughened on its sideadjacent the cathode to increase its area. With the construction of thistype the amplifica tion factor of the vacuum tube is increased and bythe elimination of the necessity of the grid bias the cost of thecircuits associated with such a device is reduced. It is of courseunderstood that the filament in each case may be thoriated or coatedwith an electronically active substance. In the constructions shown inFigs. 1 and 2 the electrons flow directly to the plate under theinfluence of the grid field without passing through the grid.

I am of course well aware" that the princ-iples of construction andoperation of this 10 invention may be applied in other physical formswithout departing from the spirit and scope of, the invention, and I donot, therefore, desire to be strictly limited to the disclosure as givenfor purposes of illustration, but rather .to the scope of the appendedclaini.

'iWhat I seek to secure by United States Letters Patent is: v i 7 An'audion c'oinprising an evacuated vessel, a cathodewithin said vessel,an open ended insulating sleeve surrounding the cathode, a

grid surrounding the sleeveand an anode in alignment with the cathodeopposite the open endof the sleeve. V

a In testimony whereof I have hereunto set rlny hand on this 3rd day ofDecember A. D.,

929,, v v I v FREDERICK W. HOCHSTETTER;

